Water pumps all come with a hole in them. They need the weep hole to warn you when seals are about to fail in the pump. The weep hole is intended to allow extra lubricant from the pump bearings to drip out of the water pump housing. Without this hole, the oil would be forced past the water pump seal and get into the engine coolant. The hole also allows coolant to escape the pump housing instead of being forced past the oil seals to contaminate the bearings.
Seal failure:
The way you can tell if a seal if about to fail is by checking the weep hole to see what is coming out If oil comes out of the weep hole, it means you have a blown or failing oil seal. If, instead, water or anti-freeze leaks out of the weep hole, then you have a leaking internal water pump seal in the case. Small amounts of moisture or oil around the weep hole is probably not a problem, but if there is significant leakage of water or oil, it is time to replace the water pump.
Some manufactures allow a certain amount of leakage from the weep hole, if it is just showing signs of dried coolant, I would not be very concerned, but if it is flowing freely and you need to top up the coolant, you will have a problem with the pump. Are you using genuine or after market pumps? I would probably go with a genuine pump if the aftermarket is being a problem.
This is all assuming that the leak is from the water pump weep hole and not the weep hole in the bottom of the timing cover. According to the picture attached below it doesn't look like there is any other sources of coolant in the front of the engine. Did you get the sealing surface clean? Are you buying quality pumps or less expensive reman units?
Image (Click to make bigger)
SPONSORED LINKS
Monday, December 4th, 2017 AT 6:26 PM